The big attraction for me with smartphones was the ability to write my own programs on them. While this is still true (less true for iOS, but that's my opinion) there are issues with smartphones that I don't want to deal with (privacy, software bloat etc.). Admittedly, the term 'feature phone' is a little vague but I'm referring to a device with minimal internet and multimedia capabilities but not to the to the extent of smartphones - a poor man's smartphone, if you will.<p>Is there a programmable feature phone which has smartphone level programmability (hopefully more) and an open OS to hack on?
I mean--"programmable feature phone with smartphone level programmability" is a contradiction in terms, but there are tons of Symbian devices and tons more that run J2ME.<p>If you want more than that, you're looking at a smartphone. Just not one you have to install much on.
Just get a device which is supported by one of the alternative Android distributions, build a stripped-down image for the thing and install it. As Android is built on top of a somewhat idiosyncratic Linux base the environment should be recognisable to anyone used to such. You can leave out any code you don't want to have on the thing, add things you do want (e.g. <i>iptables</i> configured before the network goes up, etc).<p>Using a "feature phone" with "minimal internet and multimedia capabilities" would give a false sense of privacy as the limited feature set does not negate the possibility of the device leaking all sorts of info to the outside. After all, "minimal internet" is still internet and as such can connect to anything out there. Given that even the most limited IoT-device can leak information to its true masters, a "feature phone" is hog heaven for someone looking to eavesdrop on unsuspecting users.
You could build yourself an Arduino Phone.<p>Here’s such a build, but Googling “Arduino Phone” will get you many iterations:<p><a href="http://www.instructables.com/id/ArduinoPhone-20-an-Open-Source-Mobile-Phone-Based-/" rel="nofollow">http://www.instructables.com/id/ArduinoPhone-20-an-Open-Sour...</a>
Well there's SailfishOs, which just got officially ported to Xperia X. I own a Jolla phone, which was the first to run this OS. It is open source, and I have to say quite hackable, even though I haven't tried to make any apps. Something that I find pretty cool is the fact that you can ssh into it if you enable developer mode, and you basically have a linux machine. The downsides are that the company is no longer making phones, and that there are not that many native apps for it. The upside is that it supports android 4.1.2 apps, so you are going to be covered for the most part.
Hunt on ebay for a crappy old Windows CE based phone? I've had several (before Android was a thing) and you can program in many languages on them (providing you can still find the apps - I've still got a local repository somewhere). Also the original version of Visual Studio.NET and VS 2005 both supported Windows CE as a target so you could program apps in c# and copy them over.<p>Windows CE on phones was marketed as 'Windows Mobile' and the latest version was 6.5:<p><a href="https://www.google.co.uk/search?q=window+mobile+6.5&hl=en&tbm=isch" rel="nofollow">https://www.google.co.uk/search?q=window+mobile+6.5&hl=en&tb...</a>
Maybe get an old smartphone, specifically a Nokia E-series running on the S60 platform. They can run J2ME and C++ apps, as well as Python scripts that can interact with the APIs (networking, camera, accelerometer, etc). And you could install Opera Mobile, which was actually a pretty good browser. Plus a full QWERTY keyboard.
If privacy is an issue for you then build your own phone using a raspi
<a href="https://www.raspberrypi.org/blog/piphone-home-made-raspberry-pi-smartphone/" rel="nofollow">https://www.raspberrypi.org/blog/piphone-home-made-raspberry...</a>
Try Tizen OS? Open source and the Z2 phone is so cheap! It's really a smart phone with a different OS though...<p>Not sure if it's still happening but Samsung had some developer bonuses for apps, so could be lucrative (in the short term)
Probably Librem 5 would suit, but it is still in development.<p><a href="https://puri.sm/shop/librem-5/" rel="nofollow">https://puri.sm/shop/librem-5/</a>